The reliability of a cartridge ejection device can be improved by the interposition of a readily deactivatable control flap, arranged on the outside of a monobloc unit, between a control bolt and a cartridge ejector of a break-open gun-housing of at least one barrel. The arrangement has the advantage wherein when no shot has been fired, the ejector will move into the extended position gradually during tilting of the barrel. When a shot has been fired, the ejector will remained tensioned until the barrel has been entirely tilted. Another advantageous feature is obtained by constructing the cartridge ejector of two parts coupled by way of a spring, namely a cartridge extractor and an extractor element, because thereby stress peaks can be further reduced and the cartridge extractor can already be entirely in the retracted position even before the barrel is completely closed.